Current communication between communication units within a Code Division Multiple Access (CDMA) communication system is described in detail in TIA/EIA Interim Standard IS-95A, Mobile Station-Base Station Compatibility Standards for Dual-Mode Wideband Spread Spectrum Cellular Systems, Telecommunications Industry Association, Washington, D.C. July 1993 (IS-95A) which is incorporated by reference herein. As described in IS-95A, when a reverse channel transmission rate is utilized which is less than the full rate, a discontinuous (burst type) signal is transmitted. This signal is divided into logical frames which are 20 ms (milliseconds) in length, with each frame being transmitted at a particular transmission rate. The frames are further divided into 16 smaller portions (or slots) which are referred to as power control groups. The base station demodulator estimates the energy of each power control group received from the remote unit. If the energy is above a threshold (E.sub.s) then the base station will send back a power control signal directing the remote unit to reduce its transmit power. If the energy is below E.sub.s, the power control signal will direct the remote unit to increase its transmit power.
A problem arises in the transmission rates that are not full rate, such as quarter rate. Presently, a quarter rate transmission will only transmit in a quarter, or four, of the power control groups within a frame. There will be nothing transmitted in the remaining twelve power control groups within the frame. However, the energy of the power control groups that are not used is still measured and compared to E.sub.s. This measurement results in the transmission of a power control signal from the base site to the remote unit. Currently it is up to the remote unit to keep track of which power control groups were used and to ignore power control commands that result from the energy measurement of power control groups that were not used.
A solution to this problem is described in U.S. Pat. No. (Ser. No. 08/491,336, now Pat. No. 5,629,934) POWER CONTROL FOR CDMA COMMUNICATION SYSTEMS by Ghosh et al., and U.S. Pat. No. 5,528,593 METHOD AND APPARATUS FOR CONTROLLING POWER IN A VARIABLE RATE COMMUNICATION SYSTEM by English et al. As described in Ghosh et al. and English et al., a continuous reverse channel transmission scheme is utilized for sub-rate transmission in place of IS-95A burst-type transmission. Although such continuous transmission will eliminate the need for the remote unit to ignore certain power control commands, continuous reverse channel transmission requires alternate methods for determining the transmission rate of a remote unit utilizing such a method of transmission. Therefore, a need exists for a method and apparatus for transmitting and receiving a transmission rate of a remote unit in a CDMA communication system utilizing continuous reverse channel transmission.